The present invention relates to an improvement in the means for installing prefabricated underground grease traps or grease interceptors. It is particularly suitable for use with the Trapzilla grease interceptor sold by Thermaco, Inc. of Asheboro, N.C. Trapzilla interceptors are described in U.S. Pat. No. 7,367,459 and related technology in U.S. Pat. No. 7,641,805 for solid separation. The disclosures of these two U.S. Patents are incorporated herein by reference in their entireties.
One of the ways to install such grease interceptors includes underground installation where effluent piping from a building is received in an inlet pipe of the grease interceptor. An outlet pipe to a sewage line is connected to an outlet pipe of the grease interceptor. These occur underground, with the grease interceptor buried underground. FIG. 1 shows such an underground installation with inlet 150 and outlet 152.
Such installations often occur in restaurant parking lots, which will receive vehicular traffic overhead on pavement. Access to the grease interceptor for grease removal and periodic maintenance is made through a manhole mounted in the pavement, giving access to a space above the grease interceptor, which is itself closed by a lid. Lid 20 for the grease interceptor fits on the top of an extension collar 21 as seen in FIG. 1. FIG. 1 also shows the manhole cover 18 positioned above, to be received on manhole cover ring 16.
At installation, the grease interceptor is mounted underground and concrete is poured around it to reinforce and stabilize its position. Previously, two concrete pours have been needed, one to fill up the space around the grease interceptor, stopping short of the ground level. Once the first concrete pour has been allowed to set, placement of the manhole ring 16 has followed, and a further concrete pour was needed to fill in concrete around the manhole cover 16. Sequential pours required considerable added effort, expense and trouble, since two visits to the construction site are required by the concrete delivery truck.